Wireless communication devices typified by mobile phone terminals have been modified into multiband systems, and multiple wireless devices have been installed in one wireless communication device. For example, there has been known a mobile phone terminal supporting multiple frequency bands, and multiple reception filters and multiple duplexers are installed in the mobile phone terminal.
There has been known a module including two duplexers configured so that a reception terminal to be electrically coupled to a low noise amplifier (hereinafter, referred to as LNA) is switched between the reception terminals of the two duplexers by an external switch (e.g. Japanese Patent Application Publication No. 2000-349586). Also, there has been known a module including two duplexers configured so that antenna terminals of the two duplexers are unified (e.g. Japanese Patent Application Publication No. 2010-45563).
The mobile phone terminal supporting multiple frequency bands includes large numbers of reception filters and duplexers, and thereby the number of reception filters increases and wiring arrangement becomes complicated. In recent years, use of a differential circuit has increased to form a reception circuit in an RF transceiver IC (radio frequency transceiver integrated circuit) to which a reception filter and a reception terminal of a duplexer are coupled. In this case, two reception filters and two reception terminals of the duplexer are provided with respect to one reception band, and thus the wiring arrangement becomes further complicated. In addition, increase in numbers of reception filters and duplexers causes a filter module in which the reception filters are installed and a duplexer module in which the duplexers are installed to grow in size.
Moreover, an LTE (Long Term Evolution) system has recently started, and thus the number of frequency bands to be supported by one mobile phone terminal further increases because the LTE method often uses a unique frequency band. Therefore, reception filters and duplexers further increase, and thereby the wiring arrangement becomes further complicated and the filter module and the duplexer module further grow in size.
The above problems may be solved by configuring the reception filter and the duplexer to be tunable. However, when an acoustic wave filter is used for the reception filter and the duplexer, they are difficult to be configured to be tunable.